Data Sheet
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User Manual (1.0.17)  EasyVR 3 (Plus)  11 
These are applicable to pin RX_P. 
Symbol 
Parameter 
Min 
Typ 
Max 
Unit 
V
OH
Output High Voltage (I
OH
 = -5 mA) 
2.4 
3.0 
V 
V
OL
Output Low Voltage (I
OL
 = 8 mA) 
0.0 
0.6 
V 
These are applicable to pins IO1 – IO6. 
Symbol 
Parameter 
Min 
Typ 
Max 
Unit 
V
IH
Input High Voltage 
2.4 
3.0 
3.3 
V 
V
IL
Input Low Voltage 
-0.1 
0.0 
0.75 
V 
I
IL
Input Leakage Current (0 < V
I
 < 3V, Hi-Z Input) 
<1 
10 
µA 
R
PU
Pull-up Resistance 
Strong 
10 
kΩ 
Weak 
200 
kΩ 
V
OH
Output High Voltage (I
OH
 = -5 mA) 
2.4 
3.0 
V 
V
OL
Output Low Voltage (I
OL
 = 8 mA) 
0.0 
0.6 
V 
Serial Interface 
The  EasyVR  3  communicates  via  an  asynchronous serial  interface  (commonly  known  as  UART interface), 
with the following features: 
  Baud Rate: 9600 (default), 19200, 38700, 57600, 115200 
  Frame: 8 Data bits, No parity, 1 Stop bit 
The receiver input data  line is  RX, while the transmitter output data line is  TX. No handshake lines are 
used. 
Example of a serial data frame representing character “A” (decimal 65 or hexadecimal 41): 
VCC 
Idle 
Start 
1 
0 
0 
0 
0 
0 
1 
0 
Stop 
Idle 
0V 
See also chapter Communication Protocol later on this manual for communication details. 










